According to ICH guideline S7B, in vitro electrophysiological testing of compounds against hERG should be used as part of an integrated risk assessment of QT prolongation. This recommendation was introduced after the FDA withdrew terfenadine, astemizole, terodiline, grepafloxacin, cisapride, prenylamine, sertindole and droperidole from the US market following reports of ventricular arrhythmia and other heart malfunctions associated with these drugs. Inhibition of the myocardial hERG potassium channel can cause a prolonged QT interval in humans, the possibility of ventricular arrhythmia and, in some cases, sudden death.

Long QT

Safety Regulations